The subject invention relates to a connector and, more particularly, to a pneumatic connector.
A suspension damper provides wheel control and ride quality to a vehicle by damping vibration generated by such variables as rough road surfaces, pot holes and unbalanced tires. These dampers typically operate by transmitting applied vibrational forces to a piston movably mounted in a fluid filled chamber in the damper. As the piston strokes through the chamber, the fluid in the chamber is forced through and around the piston. The resistance of the piston to movement through the fluid in the chamber is proportional to the vibrational force applied. Accordingly, these vibrational forces are dampened, thereby reducing the amount of vibration transferred to the passenger compartment.
In order to improve the damping properties, dampers have been made with controllable features to dissipate vibrational and other forces exerted on the vehicle. These variables are communicated to the damper via a control signal, and the damper responds appropriately. The control signals are often electrical, but may also be hydraulic, pneumatic or mechanical. The control signal must be routed to the actuation device controlling the damper variations. Often, the actuation device is within the damper and sometimes within the piston. Many controllable dampers have an electric control signal routed to the piston. An example of such a damper is disclosed in U.S. Pat. No. 6,007,345 to Francis et al. Other dampers have a pneumatic control signal routed to the piston. An example of this type of damper is disclosed in U.S. Pat. No. 4,886,466 to Doherty et al.
Francis et al. disclose a damper and electrical connector system requiring electrical wires to be routed through a hollow damping rod wherein an electrical connector is connected to an actuation device, such as a solenoid valve, within a housing. The electrical connector includes a power terminal having a barrel portion extending downwardly for receiving an electrode carried in the hollow damping rod. The solenoid valve is connected to the electrode and may be opened and closed to vary the dampening of the shock absorber.
Doherty et al. disclose a combination pneumatic/electrical connector that supplies electricity and gas to a device to control the flow of fluid through the piston. The connector has pneumatic and multiple electrical interfaces contained within a single pair of connectors that may be mated such that the pneumatic and multiple electrical interfaces are completed simultaneously when the two connectors are mated.
Both of the connectors are compact enough to fit in a hollow piston rod of a suspension strut or shock absorber. However, these connectors are complicated in design and limited in their application. The prior art connectors can only be packaged in certain types of dampers. In addition, as a consequence of the complicated design, the connectors of the prior art are costly to manufacture and maintain. Further, the connectors of the prior art are difficult to diagnose in a service application.
It is desirable to provide a pneumatic connector that routes only a pneumatic signal into a hollow damper rod.
The invention provides a damper assembly comprising a housing defining an inner chamber with a damping fluid disposed therein. A piston rod is slidably retained by the housing, and at least partially extends into, the chamber. A piston is disposed at a first distal end of the piston rod and strokes inside the housing. The piston defines a first chamber and a second chamber within the housing and includes at least one aperture for allowing damping fluid to flow between the first and second chambers. An actuator is disposed within the piston for varying the flow of damping fluid through the aperture between the first and second chambers within the housing. The piston rod includes an inner bore that receives pressurized air from an external source for communicating pneumatic control signals to the actuator.
The connector of the present invention is simplified over the prior art by routing pneumatic signals into a hollow damper rod to control the flow of fluid through a piston, while isolating the signal from atmospheric pressure. In addition, the pneumatic connector of the present invention may incorporate an integral flow restrictor for filtering the pneumatic signal supplied from an external source. Moreover, the pneumatic connector of the present invention has a broad application and may be packaged in various types of dampers.